Mental health articles

Biological sex and infant development
The majority of neonates are designated either male or female at birth, or
prenatally with the use of ultrasound technology. Biological sex has profound
implications for infant development for complex reasons. First, there is
increasing evidence of difference in male and female brain differentiation, although
the extent to which this directly influences observable sex differences in behaviour and psychological functioning is unclear. Second, caregivers have their
own sets of beliefs and expectations about male and female infants, which influence
their perceptions of and interactions with their infants. Finally, different social
and cultural groups have complex and variable expectations and definitions of
masculinity and femininity, which define appropriate behaviours, personality
attributes and social roles. These definitions change over time. Infants develop a
sense of gender identity or a self-definition as male or female in the first two to three years of life, and this is influenced by biological, psychological and
sociocultural factors. There are ongoing debates over the relative importance of these factors in producing observable differences between males and females but
it is clear that differences are evident in infancy.